System including an electric motor and transmission of sensor data

Abstract

A system includes an electric motor having a terminal box into which a three-phase power cable is guided and in which the stator winding, e.g., the wire ends of the winding wire of the stator winding, of the electric motor is electrically connected to electrical lines of the three-phase power cable. A data collector is arranged in the terminal box of the electric motor, which has a data store and which is electrically connected to at least one sensor arranged in and/or on the electric motor, and the data collector has an electronic circuit for the modulation and demodulation of voltage portions.

The invention claimed is: 
     
       1. A system, comprising:
 an electric motor having a terminal box into which a three-phase power cable is arranged and in which a stator winding and/or wire ends of a winding wire of the stator winding of the electric motor is electrically connected to electrical lines of the three-phase power cable; 
 wherein a data collector is arranged in the terminal box of the electric motor, includes a data storer, and is electrically connected to at least one sensor arranged in and/or on the electric motor; 
 wherein the data collector includes an electronic circuit adapted to modulate and demodulate voltage portions; 
 wherein the data storer is adapted to store values of a physical quantity detected by the sensor, which are transmittable via the electrical lines of the three-phase power cable by the modulation to a signal electronics arranged in a switch cabinet and having an electronic circuit adapted to modulate and demodulate further voltage portions; and 
 wherein the signal electronics arranged in the switch cabinet includes an inverter arranged in the switch cabinet and adapted to be fed from an AC supply network, the signal electronics being adapted to generate pulse-width modulated drive signals for controllable semiconductor switches of the inverter. 
 
     
     
       2. The system according to  claim 1 , wherein the data storer is adapted to store values of a physical quantity detected by the sensor, which are transmittable via the electrical lines of the three-phase power cable by the modulation. 
     
     
       3. The system according to  claim 1 , wherein the converter is adapted to supply the electric motor with a three-phase current by the three-phase power cable, a frequency of the three-phase current being smaller than a frequency of the voltage portions. 
     
     
       4. The system according to  claim 3 , wherein a frequency of the three-phase current is smaller than 1 kHz. 
     
     
       5. The system according to  claim 1 , wherein the modulation and demodulation of the voltage portions occurs in one or more first time periods, and the electric motor is not supplied in the first time period or periods and the data collector is supplied from an energy storage of the data collector, the inverter adapted to supply the electric motor with the three-phase current in one or more second time periods, the first time period or periods not overlapping with the second time period or periods. 
     
     
       6. The system according to  claim 1 , wherein the terminal box is arranged integrally and/or in one piece with a housing part of the electric motor and/or is detachably connected to the hosing part of the electric motor. 
     
     
       7. The system according to  claim 1 , wherein another sensor, located outside the electric motor and the terminal box, is connected to the data collector. 
     
     
       8. The system according to  claim 1 , wherein the data storer of the data collector is adapted to store: (a) a value of a temperature detected by a sensor arranged in the stator winding; (b) a value of a power frequency of an AC supply network; (c) a number of revolutions of a rotor shaft; and/or (d) a value representing hours of operation. 
     
     
       9. The system according to  claim 7 , wherein the other sensor includes an accelerometer. 
     
     
       10. A system, comprising:
 an electric motor having a terminal box into which a three-phase power cable is arranged and in which a stator winding and/or wire ends of a winding wire of the stator winding of the electric motor is electrically connected to electrical lines of the three-phase power cable; 
 wherein a data collector is arranged in the terminal box of the electric motor includes a data storer, and is electrically connected to at least one sensor arranged in and/or on the electric motor; 
 wherein the data collector includes an electronic circuit adapted to modulate and demodulate voltage portions; and 
 wherein the modulation and demodulation of the voltage portions takes place in the range of one or more zero crossings of a motor phase current. 
 
     
     
       11. The system according to  claim 10 , wherein the data storer is adapted to store values of a physical quantity detected by the sensor, which are transmittable via the electrical lines of the three-phase power cable by the modulation to a signal electronics arranged in a switch cabinet has an electronic circuit adapted to modulate and demodulate further voltage portions. 
     
     
       12. A system, comprising:
 an electric motor having a terminal box into which a three-phase power cable is arranged and in which a stator winding and/or wire ends of a winding wire of the stator winding of the electric motor is electrically connected to electrical lines of the three-phase power cable; 
 wherein a data collector is arranged in the terminal box of the electric motor, includes a data storer, and is electrically connected to at least one sensor arranged in and/or on the electric motor; 
 wherein the data collector includes an electronic circuit adapted to modulate and demodulate voltage portions; and 
 wherein a frequency of the voltage portions is higher than a frequency of the three-phase current transmitted by the three-phase power cable and/or is higher than 1 kHz. 
 
     
     
       13. A system, comprising:
 an electric motor having a terminal box into which a three-phase power cable is arranged and in which a stator winding and/or wire ends of a winding wire of the stator winding of the electric motor is electrically connected to electrical lines of the three-phase power cable; 
 wherein a data collector is arranged in the terminal box of the electric motor, includes a data storer, and is electrically connected to at least one sensor arranged in and/or on the electric motor; 
 wherein the data collector includes an electronic circuit adapted to modulate and demodulate voltage portions; 
 wherein the data storer is adapted to store values of a physical quantity detected by the sensor, which are transmittable via the electrical lines of the three-phase power cable by the modulation to a signal electronics arranged in a switch cabinet and having an electronic circuit adapted to modulate and demodulate further voltage portions; 
 wherein the electric motor is adapted to be supplied directly from an AC supply network by the three-phase power cable, and a switch and/or a line contactor is arranged between the three-phase power cable and the AC supply network; and 
 wherein the signal electronics arranged in the switch cabinet is adapted to modulate voltage portions onto the electrical lines or demodulate them from the electrical lines by the electronic circuit to modulate and demodulate voltage portions and are connected via a network and/or the Internet to a computer for data exchange. 
 
     
     
       14. The system according to  claim 13 , wherein the computer adapted to evaluate data stored in the data store. 
     
     
       15. The system according to  claim 13 , wherein a frequency of the modulated or demodulated voltage portions is greater than a frequency of the three-phase current provided by the AC supply network. 
     
     
       16. A system, comprising:
 an electric motor having a terminal box into which a three-phase power cable is arranged and in which a stator winding and/or wire ends of a winding wire of the stator winding of the electric motor is electrically connected to electrical lines of the three-phase power cable; 
 wherein a data collector is arranged in the terminal box of the electric motor, includes a data storer, and is electrically connected to at least one sensor arranged in and/or on the electric motor; 
 wherein the data collector includes an electronic circuit adapted to modulate and demodulate voltage portions; 
 wherein the data storer of the data collector is adapted to store: (a) a value of a temperature detected by a sensor arranged in the stator winding; (b) a value of a power frequency of an AC supply network; (c) a number of revolutions of a rotor shaft; and/or (d) a value representing hours of operation; and 
 wherein the value of the power frequency of the AC supply network is detected by a voltage detection sensor arranged in the data collector. 
 
     
     
       17. A system, comprising:
 an electric motor having a terminal box into which a three-phase power cable is arranged and in which a stator winding and/or wire ends of a winding wire of the stator winding of the electric motor is electrically connected to electrical lines of the three-phase power cable; 
 wherein a data collector is arranged in the terminal box of the electric motor, includes a data storer, and is electrically connected to at least one sensor arranged in and/or on the electric motor; 
 wherein the data collector includes an electronic circuit adapted to modulate and demodulate voltage portions; 
 wherein the data storer of the data collector is adapted to store: (a) a value of a temperature detected by a sensor arranged in the stator winding; (b) a value of a power frequency of an AC supply network; (c) a number of revolutions of a rotor shaft; and/or (d) a value representing hours of operation; and 
 wherein the value representing the hours of operation is detected by a time determination device adapted to determine a duration of a non-vanishing motor voltage provided via the three-phase power cable. 
 
     
     
       18. A system, comprising:
 an electric motor having a terminal box into which a three-phase power cable is arranged and in which a stator winding and/or wire ends of a winding wire of the stator winding of the electric motor is electrically connected to electrical lines of the three-phase power cable; 
 wherein a data collector is arranged in the terminal box of the electric motor, includes a data storer, and is electrically connected to at least one sensor arranged in and/or on the electric motor; 
 wherein the data collector includes an electronic circuit adapted to modulate and demodulate voltage portions; 
 wherein the data storer of the data collector is adapted to store: (a) a value of a temperature detected by a sensor arranged in the stator winding; (b) a value of a power frequency of an AC supply network; (c) a number of revolutions of a rotor shaft; and/or (d) a value representing hours of operation; and 
 wherein the number of revolutions of the rotor shaft and/or a number of regulation of the rotor shaft since a beginning of operation of the electric motor is determined by evaluating a signal of a sensor that detects the number of periods of the voltage supplying the electric motor. 
 
     
     
       19. A system, comprising:
 an electric motor having a terminal box into which a three-phase power cable is arranged and in which a stator winding and/or wire ends of a winding wire of the stator winding of the electric motor is electrically connected to electrical lines of the three-phase power cable; 
 wherein a data collector is arranged in the terminal box of the electric motor, includes a data storer, and is electrically connected to at least one sensor arranged in and/or on the electric motor; 
 wherein the data collector includes an electronic circuit adapted to modulate and demodulate voltage portions; 
 wherein the data storer of the data collector is adapted to store: (a) a value of a temperature detected by a sensor arranged in the stator winding; (b) a value of a power frequency of an AC supply network; (c) a number of revolutions of a rotor shaft; and/or (d) a value representing hours of operation; and 
 wherein the number of revolutions of the rotor shaft and/or the number of revolutions of the rotor shaft since a beginning of operation of the electric motor is determined from a count of a counter that counts zero crossings of a phase current or of motor current of the electric motor. 
 
     
     
       20. A method for operating a system that includes an electric motor having a terminal box into which a three-phase power cable is arranged and in which a stator winding and/or wire ends of a winding wire of the stator winding of the electric motor is electrically connected to electrical lines of the three-phase power cable, a data collector being arranged in the terminal box of the electric motor, including a data storer, and being electrically connected to at least one sensor arranged in and/or on the electric motor, the data collector including an electronic circuit adapted to modulate and demodulate voltage portions, comprising:
 performing modulation and demodulation of the voltage portions in one or more first time periods; and 
 supplying the electric motor with electrical power for generating mechanical torque in one or more second time periods; 
 wherein the first time period or periods do not overlap with the second time period or periods.